The present invention relates in general to a communication system for carrying out a hand-over which is requested from a radio base station due to the movement of a mobile station, and more particularly to a packet communication system for managing packet signals and an Asynchronous Transfer Mode (ATM) system for managing cell signals.
In recent years, high reliability has been required for a public communication network for transmitting data relating to voice and images. Nowadays having entered the multimedia era, data is transmitted for example utilizing mobile communications. Hence for mobile communication, high reliability has been required when carrying out the hand-over of calls.
A discussion of the hand-over of call is provided, for example, by the reference "Mobile Communication Network, the 12th series of Information Network", by Mitsuo Yokoyama, Shokoudou.